Gun sight



l 2, 1946. R. R. vouGHT GUN S I GHT `Filed Jan. 17, 1 941 Patented Apr. 2, 1946 i y assign.

GUN.sieriixr' I Russelll R; Vou'ght, Beverly HillsgCalit Application, Januaryv 17, 194'1; SerialaNo. 37:4;853; (cl. 33-455).

'3' 'Claigns This inventionl pertains 'to an improved; gun. sight particular-1y adapteda'for -useon xiiilitaryv air.,- crat such as dive Ibombers. Generally-stated; the invention comprises; "aL combined. agun fsight and dive 'indicator whereby` therpiilotgor operator may not only 'properly-'direct planeA at; the target but' in :additioni execute thee dive Ib iznnbing attack at l1a predetermined; and; desired; diving angle so that planewisnmder predetermined and optimum Yconditionsifer 'thesuccessful;.cem-y pletion. .off the vvdive 'bomhing. attack; anda` :proper: pull-out without; imposingv unnecessary strain; uponthepilotorhis plane., l

In. dive bombing ther-:plane carrying'the'bomb dives at .high speed from axhighpaltitude.the;axis of the yplane .being .directedupontthe target; Dur-f ing .the latter`- courseioifthedivmthe pilot or;` operator must' accurately .follaw,= the target; andv direct the axis of Ahisfd-iveifataprecisezpdinti on or immediately ahead: off-the target',A At. aspredeter- 'mined minimum. altitude 'above the target the bombs are released and theplane'rapidlychanges its coursepulling cutA caf-the` dive andiaway from the target., 'Bhevlbombs continuefa'long'a; line,- of travel Whiclrisfan extensionfof theidilenticn-of` the planes diving attack andrerexptedto hit t'hB 1 target,

Very often vznllilit :becomes 'englOSSe in the problemof maintaining theuaxist'ofwhis planedifrented at the target yandenes#:find himself; either; diving at a 90",* angle;` (perpendicular. tothe hon zontal) or. at annnglejinexcess of: 9.0.9, under which conditions the plane is Virtuwllyfonf-its5back;

Diving under such conditions is dangerous; and the pull-out is extremely haizardous, in that; it subjects they pilot; and the-plane to tremendous centrifugal forceswhich mayvv destroy y'the p lane itself `ror at least, causeA the pilot todose,conscious-rr ness yfor a prolonged` period oi time, with some?- times disastrous. results.

The present invention ,is .directedtoa gun .sight which is employed by. the pfilotn-c'iur'ingl the dive and which includes a. dive indicator.,[thereby per` mitting the pilot not only to accurately direct, the course of his piane but Yat thesame time Vmaintain 'a desired angle ofdive. Atl all" events, the pilot is informed`- as to when he reaches 'the pre;- ferred angle of attack without having to remove his eyes fromthe g-un'sig'ht; Iti'sftobe 4re'rnexnbered that during-a divingf attack 'iti 4is essential for the pilot' Atoemaintain:hisfeyes onv the target' and that.` if, it' is. necessanyfforehim. f'tofmove his 4 6fach telescopios-ight equipped withi the,1 means 'ofi thisv invention;V

Eig: '3.a is; antransverse.f,section; taken.V along.; the plane III-III fof;1iis:,2.

Eig; i4 :isaesectienataken alongzthe plane2 Ill-IV ois-"Eig-.

Eig: I5` is 1an isometricmepresentationofi the main elements ci `thedive;indidatmt lin improv-edf form.

In Mez. 1g the:etiiplerie I; isfelcecutingv a 'dive at'. anemglegl of@A H0? to; the;` horizonte-L and 'for the.- purpeses ofrthlssidiseussinn;itmayf'berassumedthat. mi :is.-tlie'f.preferliedangglegof' attack` during 'dive bombing;- llt-n wilhbevevident; thatiifthe4 angle; ofi

attack; increased: to say 9m or therebeyond;

it is mo'e diicult for the pilot tdcontrol his plane,l

and the dangers ofipull-foutiare f-greatlyinereased,

During.; the-dive: ,the;.pilotxdire.cts i his plane by therese; fof'ta fgun; sightgeneraliyf indicated at thisgumsight-` beingenfintegral partv oithe plane: l, the axis of the sight 2 being parallel toithe;

amsfofftheajplanei vAflongitudinal section through ate1escopic gunfs-ightgis shownfin Figs2f'andas there: shown the` sight, comprises a" barrelVV pro# videdswithanplurality:ofilenses; such asthe ob-V A1 iectives-1-4-and`5 andthe voculare-6'; and l. reticuley-glass is; indicated-:fat Brand ai l-resilient on yielding'eyeprestis;indica,ted;ret19= Attached:toftheftubnlarfbodmofthe' vgun` sight` Lis.: a.. housing.,l im containing; a.: dive indicator whosefindexmember; 'H- vextends through a suitablezonenine on slit;112;formedrin'tthefsideyof the tubular body portion of the telescopigun sight;

zat aspointiicloselm addacentstheffreticule glass 8 aindffnreferablybetweentthenreticuleglassiandaeye; pieceofithe.:sight: ,meshcwnzfmonea pmzticulariy' infr-E393; -llrfzmeygfnormally-wlieg im indicated- L-duttedf :lines l therefore out of the central portion of the eld of view through the telescope Its presence would ordinarily not be observed by the user of the sight In the event the aircraft on which theV gun sight is mounted is executing a dive at an 3 angle of 70, the index member II will occupy `ried by the shaftV I1.

1 the shaft I1. f

` I9. the chamber I9 stops' or anti-splashibailles, such as the baffles 3l and v32, may be providdthese Y bailles or stops being suitably r'etic'zulated'orA per- These baiiles prevent violent surging of the liquid within the chamber' ISIWithoutprethe Afull line position shown in Fig. 3 and thereby inform. the pilot as to his diving angle while the I pilot is observing the target through his sight.

The dive indicator associated with the gun sightY 1 should include, in-addition to an indicator movfable substantially in the focal plane of the sight,

some damping means whereby minute variations A Yresistancerof the dive indicator may be modified or shifts in the angle of attack are not immedi- `ately indicated. `Damping means thus prevent'. `the indicator from'fluttering or vibrating unnecessarily.. Furthermore, in'interests of economy and simplicity, it is desirable that the in- 3 and 4, the auxiliary,l housing I0 contains a jack shaft I4 on which the indicator II is mounted.

is in engagement with another spiral geary I6 car--l The shaft I'I extends through aY gland. orioil-.tight bearing I8 into a the unbalanced member 24 will hang downwardly Vlout the housing I0 and telescopic sight will be inclined so that the baille 32 will be very much closer to the member 24. The movement of the member 24 within the body of liquid in the chamber I9 is impeded somewhat by the damping uid within the chamber. The bores or perforations 25 and 26 permit iiuid to pass through the uns balanced member 24, the amount of resistance or the extent of the dampingeffect dependingr somewhat upon the'viscosity. of the `fluid within the chamber and the number and size of the perfoy rations 25 and 26 formed in the member 24; The

by changing the fluid and by changing the number and size of ports in the unbalanced member.v The damping is particularly desired at idly changes its angle .of attack from 0 to The shaft I4 also includesa spiral gear I5 which chamber I9. vThe chamber I9 may be capped,l

with a removableend member 20 carrying a bearing adapted to receive the end of the eshaft Il. The other end of the shaft may be journaled in The'shaft I'I is shown I the like, these apertures havingoutwardly flar-` ing side walls leading to a restricted bore.

The chamber I9 is preferably iilled with a nonfreezing liquid whose viscosity characteristics are not materially altered or changed due to variations in temperature. Preferred Aliquids should have a freezing point well below 40 F. and l should not exhibit material changes in viscosity at temperatures ybetween-about -40 F. and 80"v Moreover, theY preferred liquids should not vaporize readily.v Y There "are, various liquids say 70 and it is important that this rapid change in the axis ofv the aircraft be absorbed without setting up unnecessary.'oscillations of the unbalancedmember 24..V

The schematic arrangement shown in. Fig. 5 shows an unbalanced member 24 but the shaft on Iwhich this unbalanced :member is mounted, and indicated at 31is providedwith .a crank38 connected as by means of. a link36 to the index mem- Vber 35 which is pivoted at `341. The link 36 is attached to the'end of index-member 35 and to the crank 38 by smalluniversal or toggle `joints. This simple form of construction eliminates the use of gears such as the gears I5 and I6, and may be entirely satisfactory for use in training planes.

As previously pointed out, the present inventionV permits the pilot of the plane to maintain his target in sight and at the same time know when hel has reached or lsexceeding the predetermined angle of dive. The critical diving angle as well as other divingV angles approximating the Y critical I angle may be engraved or marked upon the retiadapted for use under the conditions encouny tered, among them beingglycol derivatives, tetradecane, quinoline, octyl alcohol, phenyl isothicyanate, and solutions of bromates and iodides, etc. Y

It is to be understood that the form of the in- Y 1 vention hereV specifically described is simply illustrative of one formY that the invention may take,

and that numerous changes and modifications can be made, as will vbe. evident to skilled workersin the art. 'l

The chamber I9 maybe provided with a relatively large fillingV Vcap 30 through which'the clamping liquid maybe introduced, therneck of.

said filling port beingA` sufliciently long so as to permit the liquid Ato completely fill thechamber Extending inwardly from the sideV wallsgof forated.

ventingcirculation.

Those skilled in the art will cule glass 8 so as to facilitate reading of the in-- The extent of movement of the dex member II. index member wil1,of course, depend upon the size of the port I2and upon the gear ratio between thegearslandl.

Although vagspecific 4form of the invention has been described, it is to be'understood that the invention is not limited thereto, theY exemplary form being described simply forpurposes of i1- lustration. All changes and modications com f ing `within the scope-of. the appended claims are embraced thereby.

/Iclairm Y 1. InV combination with a gun sight xedly mounted on an aircraft: a housing flxedly attached to the gunsight; gravity responsive actuating means in'said housing, said actuating means being'movable in a plane'parallel tothe axis of Y with respect .to the'barrelv of the gun sight; an Y indicator member extending from' saidliousing into said barrel and movablein Va plane transverse' to the optical axis of said lens system; gravity responsive means in said housing, said means being movable in a plane parallel to the axis of the gun sight and about an axis perpendicular to the optical axis of the gun sight; and means for translating movement of the gravity responsive means into movement of the indicator.

3. Gravity responsive means for indicating the inclination of a telescopic gun sight iixedly i0 mounted on an aircraft, comprising: a housing adapted to be fixedly attached to the tube of the gun sight; gravity responsive actuating means in said housing, said actuating means being movable in a plane parallel to the axis of the gun sight and about an axis perpendicular to the optical axis of the gun sight; and an indicator member operably attached to the gravity responsive actuating means, said indicator being movable in a plane substantially perpendicular to the axis of the |gun sight and adapted to extendv from the housing into the line of sight through said gun sight.l

RUSSELL R. VOUGH'I. 

